Methods of Astronomical Observation. 193 



Reduction to the Meridian. Refraction. 



X = 55° 57 COS. 9-748123 o. ' 



a = 22° 50 COS. 9-964560 Z = 33 10 log. I d 1-5818 



A = 56° 50 sec. 0-261952 tan. 0-1847 B = 30-17 log. 0-0025 



9-974635x2=9-9493 r = 70° log. 9-9991 

 m = 214"-751og.2-3319337ilog. 9-2711 f = 68° log. 9-9840 



<?t= + 202"-57 log. 2-306568c'log. 9'405i r = 36' -93 log. 1-5674 

 c' = 0"-25 



R.M=202-32=3' 22-32. 



Reduction to the Solstice. 



h. m. s. ^ 



0's R. A. at app. noon = 6 56 8-19 at Edinburgh, w = 23° 27' 40 ' 

 Solstice, 6 . 0000 



A, or distance from solstice, 56 8-19 = 56"-1365. 

 Now by formula (B) page 10. 



Constant logarithm, 9-855576 



A = 56'"-1365 log. X 2, 3-498490 



1 = 37' 39"-78 log., 3-354066 



2 = 0-61 by small table. 



R. S. = + 37 39-17 •= reduction to the solstice. 



o 



Apparent altitude of the sun's centre, . . . 56 49 51-12 



Refraction, — 3693 



Parallax, + 4-67 



Reduction to the meridian, + 3 22-32 



„ to solstice, +37 39-17 



Latitude of the place of observation, . . . . 55 57 15-67 



Sun's latitude south, -j- 0*10 



Solar equation and reduction to January 1st, . + 0-70 



T ,. S ^ — 0-73 



Lunar equations < „ _„ 



^ t V + 0-10 



Mean obliquity, Jan. 1st, 1834 = Sum* — 90° = 23 27 36-19 

 Bessel gives, 23 27 39-26 



Error of one day's observations, — 3*07 



By a mean of ten days observations reduced in this 

 manner, the obliquity was 23°27'41"-64, and the difference 



• When the declination is of a contrary name to that of the latitude, the sum is 

 the polar distance of an opposite name, and must be subtracted from W. 

 VOL. IV. O 



